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2. 1 Origins and Evolution of HTML - HTML was defined with SGML - 2. 1 Origins and Evolution of HTML - HTML was defined with SGML - Original intent of HTML: General layout of documents that could be displayed by a wide variety of computers - Recent versions: - HTML 4. 0 – 1997 - Introduced many new features and deprecated many older features - HTML 4. 01 - 1999 - A cleanup of 4. 0 - XHTML 1. 0 - 2000 - Just 4. 01 defined using XML, instead of SGML - XHTML 1. 1 – 2001 - Modularized 1. 0, and drops frames - Although the value of the consistent and coherent syntax rules of XHTML were widely recognized and accepted, its draconian error handling was not, so XHTML documents are served as HTML - W 3 C worked on XHTML 2. 0; WHAT worked on a new version of HTML Chapter 2 © 2012 by Addison Wesley Longman, Inc. 1

2. 1 Origins and Evolution of HTML (continued) - In 2009, XHTML 2. 0 2. 1 Origins and Evolution of HTML (continued) - In 2009, XHTML 2. 0 was stopped; W 3 C took over development of HTML 5 - Reasons to use XHTML syntax rules: 1. HTML has lax syntax rules, leading to sloppy and sometimes to ambiguous documents - XHTML syntax is much more strict, leading to clean and clear documents in a standard form 2. HTML processors do not even enforce the few syntax rule that do exist in HTML 3. The syntactic correctness of XHTML documents can be validated - In this book, HTML 5 is used, but with XHTML syntax rules 2. 2 Basic Syntax - Elements are defined by tags (markers) - Tag format: - Opening tag: - Closing tag: - The opening tag and its closing tag together specify a container for the content they enclose Chapter 2 © 2012 by Addison Wesley Longman, Inc. 2

2. 2 Basic Syntax (continued) - Not all tags have content - If a 2. 2 Basic Syntax (continued) - Not all tags have content - If a tag has no content, its form is - The container and its content together are called an element - If a tag has attributes, they appear between its name and the right bracket of the opening tag - Comment form: - Browsers ignore comments, unrecognized tags, line breaks, multiple spaces, and tabs - Tags are suggestions to the browser, even if they are recognized by the browser - In XHTML, element and attribute names must be in all lowercase letters - In HTML, they can be any combination of uppercase and lowercase Chapter 2 © 2012 by Addison Wesley Longman, Inc. 3

2. 3 Standard XHTML Document Structure - Every XHTML document must begin with: <!DOCTYPE 2. 3 Standard XHTML Document Structure - Every XHTML document must begin with: - , , , and <body> are required in every document (in XHTML, not HTML) - The whole document must have <html> as its root - html must have the lang attribute: <html lang = ″en″> (this one is for English) - A document consists of a head and a body - The <title> tag is used to give the document a title, which is normally displayed in the browser’s window title bar (at the top of the display) - The meta tag is used to provide the character set used <meta charset = ″utf-8″ /> Chapter 2 © 2012 by Addison Wesley Longman, Inc. 4 </p> </div> <div style="width: auto;" class="description columns twelve"><p><img class="imgdescription" title="2. 4 Basic Text Markup - Text is normally placed in paragraph elements -" src="https://present5.com/presentation/dc67405355bc4639d787cbb5781423c2/image-5.jpg" alt="2. 4 Basic Text Markup - Text is normally placed in paragraph elements -" /> 2. 4 Basic Text Markup - Text is normally placed in paragraph elements - Paragraph Elements - The <p> tag breaks the current line and inserts a blank line - the new line gets the beginning of the content of the paragraph - The closing tag is required in XHTML, not in HTML <!DOCTYPE html> <!-- greet. html A trivial document --> <html lang = ″en″> <head> <title> Our first document

Greetings from your Webmaster!

Chapter 2 © 2012 by Addison Wesley Longman, Inc. 5

2. 4 Basic Text Markup (continued) - Line breaks - The effect of the 2. 4 Basic Text Markup (continued) - Line breaks - The effect of the tag is the same as that of

, except for the blank line (in HTML, it could be just ) - No closing tag! - Example of paragraphs and line breaks On the plains of hesitation

bleach the bones of countless millions

who, at the dawn of victory sat down to wait, and waiting, died. - Typical display of this text: On the plains of hesitation bleach the bones of countless millions who, at the dawn of victory sat down to wait, and waiting, died. - Preserving whitespace - The text content of a 
 element is displayed as it is entered Chapter 2 © 2012 by Addison Wesley Longman, Inc. 6

2. 4 Basic Text Markup (continued) - Headings - Six sizes, 1 - 6, 2. 4 Basic Text Markup (continued) - Headings - Six sizes, 1 - 6, specified with to - 1, 2, and 3 use font sizes that are larger than the default font size - 4 uses the default size - 5 and 6 use smaller font sizes Headings Aidan’s Airplanes (h 1) The best in used airplanes (h 2) "We’ve got them by the hangarful" (h 3) We’re the guys to see for a good used airplane (h 4) We offer great prices on great planes (h 5) No returns, no guarantees, no refunds, all sales are final (h 6) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 7

2. 4 Basic Text Markup (continued) - Blockquotes - Content of <blockquote> - To 2. 4 Basic Text Markup (continued) - Blockquotes - Content of

- To set a block of text off from the normal flow and appearance of text - Browsers often indent, and sometimes italicize - Font Styles and Sizes (can be nested) - Emphasis - (often set in italics) - Strong - (often set in boldface) - Monospace - (often set in Courier) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 8

2. 4 Basic Text Markup (continued) - <em>, <strong>, and <code> are not affected 2. 4 Basic Text Markup (continued) - , , and are not affected if they appear in the content of a

, unless there is a conflict (e. g. , (italics)) - Superscripts and subscripts - Subscripts with - Superscripts with Example: x23 Display: x 23 - Inline versus block elements - Block elements CANNOT be nested in inline elements (in XHTML) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 9

2. 4 Basic Text Markup (continued) - All of this font size and font 2. 4 Basic Text Markup (continued) - All of this font size and font style stuff can be done with style sheets, but these tags are not yet deprecated - Character Entities Char. Entity & < > " ' ¼ ½ ¾ & < > " ' &frac 14; &frac 12; &frac 34; ° (space)   Meaning Ampersand Less than Greater than Double quote Single quote One quarter One half Three quarters Degree Non-breaking space - Horizontal rules -

draws a line across the display, after a line break Chapter 2 © 2012 by Addison Wesley Longman, Inc. 10

2. 5 Images - Formats: - GIF (Graphic Interchange Format) - 8 -bit color 2. 5 Images - Formats: - GIF (Graphic Interchange Format) - 8 -bit color (256 different colors) - JPEG (Joint Photographic Experts Group) - 24 -bit color (16 million different colors) - Both use compression, but JPEG compression is better - Portable Network Graphics (PNG) - Relatively new - Should eventually replace both gif and jpeg - Files are bigger than jpeg – no lost data! - Images are inserted into a document with the tag with the src attribute - The alt attribute is required by XHTML - Purposes: 1. Non-graphical browsers 2. Browsers with images turned off Picture of comets - The tag has 30 different attributes, including width and height (in pixels) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 11

2. 5 Images (continued) <!DOCTYPE html> <!-- image. html An example to illustrate an 2. 5 Images (continued) Images Aidan's Airplanes The best in used airplanes "We've got them by the hangarful" Special of the month

1960 Cessna 210 577 hours since major engine overhaul 1022 hours since prop overhaul Picture of a Cessna 210 Buy this fine airplane today at a remarkably low price Call 999 -555 -1111 today!

Chapter 2 © 2012 by Addison Wesley Longman, Inc. 12

2. 5 Images (continued) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 13 2. 5 Images (continued) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 13

2. 5 Images (continued) - HTML Validation - Replace DOCTYPE with: <!DOCTYPE html PUBLIC 2. 5 Images (continued) - HTML Validation - Replace DOCTYPE with: (the anchor tag) - The content of is the visual link in the document Chapter 2 © 2012 by Addison Wesley Longman, Inc. 14

2. 6 Hypertext Links (continued) <!DOCTYPE html> <!-- link. html An example to illustrate 2. 6 Hypertext Links (continued) Links Aidan's Airplanes The best in used airplanes "We've got them by the hangarful" Special of the month

1960 Cessna 210 Information on the Cessna 210

Chapter 2 © 2012 by Addison Wesley Longman, Inc. 15

2. 6 Hypertext Links (continued) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 2. 6 Hypertext Links (continued) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 16

2. 6 Hypertext Links (continued) - If the target is not at the beginning 2. 6 Hypertext Links (continued) - If the target is not at the beginning of the document, the target spot must be marked - Target labels can be defined in many different tags with the id attribute, as in Baskets - The link to an id must be preceded by a pound sign (#); If the id is in the same document, this target could be What about baskets? - If the target is in a different document, the document reference must be included Small picture of an airplane Info on C 210 Chapter 2 © 2012 by Addison Wesley Longman, Inc. 17

2. 7 Lists - Unordered lists - The list is the content of the 2. 7 Lists - Unordered lists - The list is the content of the

    tag - List elements are the content of the
  • tag Some Common Single-Engine Aircraft
    • Cessna Skyhawk
    • Beechcraft Bonanza
    • Piper Cherokee
    - Ordered lists - The list is the content of the
      tag - Each item in the display is preceded by a sequence value Chapter 2 © 2012 by Addison Wesley Longman, Inc. 18

2. 7 Lists (continued) <h 3> Cessna 210 Engine Starting Instructions </h 3> <ol> 2. 7 Lists (continued) Cessna 210 Engine Starting Instructions

  1. Set mixture to rich
  2. Set propeller to high RPM
  3. Set ignition switch to "BOTH"
  4. Set auxiliary fuel pump switch to "LOW PRIME"
  5. When fuel pressure reaches 2 to 2. 5 PSI, push starter button
- Nested lists - Any type list can be nested inside any type list - The nested list must be in a list item Chapter 2 © 2012 by Addison Wesley Longman, Inc. 19

2. 7 Lists (continued) - Definition lists (for glossaries, etc. ) - List is 2. 7 Lists (continued) - Definition lists (for glossaries, etc. ) - List is the content of the

tag - Terms being defined are the content of the
tag - The definitions themselves are the content of the
tag Single-Engine Cessna Airplanes
152
Two-place trainer
172
Smaller four-place airplane
182
Larger four-place airplane
210
Six-place airplane - high performance
Chapter 2 © 2012 by Addison Wesley Longman, Inc. 20

2. 8 Tables - A table is a matrix of cells, each possibly having 2. 8 Tables - A table is a matrix of cells, each possibly having content - The cells can include almost any element - A table is specified as the content of a

tag - In HTML 5, tables do not have lines between the rows or between the columns - We can add those with Cascading Style Sheets, as will be discussed in Chapter 3 - Tables are given titles with the
tag, which can immediately follow Chapter 2 © 2012 by Addison Wesley Longman, Inc. 21

2. 8 Tables (continued) - Each row of a table is specified as the 2. 8 Tables (continued) - Each row of a table is specified as the content of a

tag - The row headings are specified as the content of a Chapter 2 © 2012 by Addison Wesley Longman, Inc. 23

2. 8 Tables (continued) - If the rows have labels and there is a 2. 8 Tables (continued) - If the rows have labels and there is a spanning column label, the upper left corner must be made larger, using rowspan

tag - The contents of a data cell is specified as the content of a tag
Fruit Juice Drinks
Apple Orange Screwdriver
Breakfast 0 1 0
Lunch 1 0
Chapter 2 © 2012 by Addison Wesley Longman, Inc. 22

2. 8 Tables (continued) - A table can have two levels of column labels 2. 8 Tables (continued) - A table can have two levels of column labels - If so, the colspan attribute must be set in the

tag to specify that the label must span some number of columns
Fruit Juice Drinks
Orange Apple Screwdriver
…
Fruit Juice Drinks
Apple Orange Screwdriver
Chapter 2 © 2012 by Addison Wesley Longman, Inc. 24

2. 8 Tables (continued) - Table Sections - Header, body, and footer, which are 2. 8 Tables (continued) - Table Sections - Header, body, and footer, which are the elements: thead, tbody, and tfoot - If a document has multiple tbody elements, they are separated by thicker horizontal lines - Uses of Tables - In the past, tables were used to align elements in rows and columns – general layout - That use of tables is now frowned upon - Use Cascading Style Sheets to place elements in rows and columns – general layout - Use tables only when the information is naturally tabular Chapter 2 © 2012 by Addison Wesley Longman, Inc. 25

2. 9 Forms - A form is the usual way information is gotten from 2. 9 Forms - A form is the usual way information is gotten from a browser user to a server - HTML has tags to create a collection of objects that implement this information gathering - The objects are called widgets or controls or components (e. g. , radio buttons and checkboxes) - When the Submit button of a form is clicked, the form’s values are sent to the server for processing - All of the widgets, or components of a form are defined in the content of a tag - The only required attribute of is action, which specifies the URL of the application that is to be called when the Submit button is clicked (XHTML requires it; HTML does not) action = http: //www. cs. ucp. edu/cgi-bin/survey. pl Chapter 2 © 2012 by Addison Wesley Longman, Inc. 26

2. 9 Forms (continued) - The method attribute of <form> specifies one of the 2. 9 Forms (continued) - The method attribute of specifies one of the two possible techniques of transferring the form data to the server, get and post - The default is get - Widgets - Many are created with the tag - The type attribute of specifies the kind of widget being created 1. Text - Creates a horizontal box for text input - Default size is 20; it can be changed with the size attribute Chapter 2 © 2012 by Addison Wesley Longman, Inc. 27

2. 9 Forms (continued) - If you don’t want to allow the user to 2. 9 Forms (continued) - If you don’t want to allow the user to type more characters than will fit, set maxlength, which causes excess input to be ignored - Widgets should be placed in label elements 2. Password – just like text except asterisks are displayed, rather than the input characters 3. Checkboxes - to collect multiple choice input - Every checkbox requires a value attribute, which is the widget’s value in the form data when the checkbox is ‘checked’ - To initialize a checkbox to ‘checked’, the checked attribute must be set to "checked" Chapter 2 © 2012 by Addison Wesley Longman, Inc. 28

" src="https://present5.com/presentation/dc67405355bc4639d787cbb5781423c2/image-29.jpg" alt="2. 9 Forms (continued) - Widgets (continued) Grocery Checklist

" /> 2. 9 Forms (continued) - Widgets (continued) Grocery Checklist

Eggs

4. Radio Buttons - collections of checkboxes in which only one button can be ‘checked’ at a time - Every button in a radio button group MUST have the same name Chapter 2 © 2012 by Addison Wesley Longman, Inc. 29

2. 9 Forms (continued) - Widgets (continued) 4. Radio Buttons (continued) - If no 2. 9 Forms (continued) - Widgets (continued) 4. Radio Buttons (continued) - If no button in a radio button group is ‘pressed’, the browser often ‘presses’ the first one Age Category

20 -35 36 -50 Over 50

Chapter 2 © 2012 by Addison Wesley Longman, Inc. 30

2. 9 Forms (continued) -Widgets (continued) 5. The <select> tag - There are two 2. 9 Forms (continued) -Widgets (continued) 5. The is required - The size attribute of (continued) - Each item of a menu is specified with an

With size = 1 (the default)

Chapter 2 © 2012 by Addison Wesley Longman, Inc. 32

2. 9 Forms (continued) - Widgets (continued) - After clicking the menu: - After 2. 9 Forms (continued) - Widgets (continued) - After clicking the menu: - After changing size to 2: Chapter 2 © 2012 by Addison Wesley Longman, Inc. 33

2. 9 Forms (continued) -Widgets (continued) 6. Text areas - created with <textarea> - 2. 9 Forms (continued) -Widgets (continued) 6. Text areas - created with

Chapter 2 rows = "3” © 2012 by Addison Wesley Longman, Inc. 34

2. 9 Forms (continued) - Widgets (continued) 7. Reset and Submit buttons - Both 2. 9 Forms (continued) - Widgets (continued) 7. Reset and Submit buttons - Both are created with - Submit has two actions: 1. Encode the data of the form 2. Request that the server execute the server-resident program specified as the value of the action attribute of

- A Submit button is required in every form SHOW popcorn. html and display it Chapter 2 © 2012 by Addison Wesley Longman, Inc. 35

2. 10 HTML 5 - Using HTML 5 is a bit premature, because there 2. 10 HTML 5 - Using HTML 5 is a bit premature, because there are still many browsers in use that do not support it - Code can be included in a document to detect HTML 5 features and produce a message to the user – This is covered in Chapter 4 - The audio Element - Prior to HTML 5, a plug-in was required to play sound while a document was being displayed - Audio encoding algorithms are called audio codecs – e. g. , MP 3, Vorbis - Coded audio data is stored in containers—e. g. , Ogg, MP 3, and Wav (file name extension indicates the container, not the audio code) - Vorbis code is stored in Ogg containers - MP 3 code is stored in MP 3 containers - Wav code is stored in Wav containers Chapter 2 © 2012 by Addison Wesley Longman, Inc. 36

2. 10 HTML 5 (continued) - The audio Element (continued) - General syntax: <audio 2. 10 HTML 5 (continued) - The audio Element (continued) - General syntax: - Browser chooses the first audio file it can play and skips the content; if none, it displays the content - Different browsers have different audio capabilities - The controls attribute, which is set to "controls“, creates a start/stop button, a clock, a progress slider, total time of the file, and a volume slider Chapter 2 © 2012 by Addison Wesley Longman, Inc. 37

2. 10 HTML 5 (continued) - The audio Element (continued) <!DOCTYPE html> <!– audio. 2. 10 HTML 5 (continued) - The audio Element (continued) Test audio element This is a test of the audio element Chapter 2 © 2012 by Addison Wesley Longman, Inc. 38

2. 10 HTML 5 (continued) - The video Element - Prior to HTML 5, 2. 10 HTML 5 (continued) - The video Element - Prior to HTML 5, there was no standard way to play video clips while a document was being displayed - Video codecs are stored in containers - Video codecs: H. 264 (MPEG-4 AVC) – can be stored in an MPEG-4 container Theora – can be stored in any container VP 8—can be stored in any container - Different browsers support different codecs - The width and height attributes set the screen size - The autoplay attribute, set to "autoplay", specifies that the video should play as soon as it is ready - The preload attribute, set to "preload", specifies that the video should be loaded as soon as the document is loaded -The controls attribute, set to "controls", is like that of the audio element Chapter 2 © 2012 by Addison Wesley Longman, Inc. 39

2. 10 HTML 5 (continued) - The video Element (continued) <!DOCTYPE html> <!-- testvideo. 2. 10 HTML 5 (continued) - The video Element (continued) test video element This is a test of the video element. . . Chapter 2 © 2012 by Addison Wesley Longman, Inc. 40

2. 10 HTML 5 (continued) - Organizational Elements - Header Elements - hgroup – 2. 10 HTML 5 (continued) - Organizational Elements - Header Elements - hgroup – a container for header information

The Podunk Press ″All the news we can fit″
-- table of contents –
- Footer Elements - footer – a container footer information
© The Podunk Press, 2012 Editor in Chief: Squeak Martin
- The section Element – a container for sections - The article Element – a container for self-contained part of a document (from another source) - The aside Element – a container for tangential info - The nav Element – navigation sections (list of links) Chapter 2 © 2012 by Addison Wesley Longman, Inc. 41

2. 10 HTML 5 (continued) - The time Element - For putting a time 2. 10 HTML 5 (continued) - The time Element - For putting a time stamp on a document - Two parts, text and machine-readable (datetime) - datetime attribute (optional) – the machine-readable part - Date part: 4 -digit year, a dash, 2 -digit month, a dash, 2 -digit day of the month (″ 2012 -08 -29”) - Time (optional) format: T 09: 00 - Text part is given as the content of time - The two parts need not specify the same date - Deficiencies: 1. Dates prior to the Christian era are not possible 2. No approximations Chapter 2 © 2012 by Addison Wesley Longman, Inc. 42

2. 11 Syntactic Differences between HTML & XHTML - Case sensitivity - Closing tags 2. 11 Syntactic Differences between HTML & XHTML - Case sensitivity - Closing tags - Quoted attribute values - Explicit attribute values - id and name attributes - Element nesting Chapter 2 © 2012 by Addison Wesley Longman, Inc. 43